Belt change fun

Just changed the cam belt on my Mk1 MX5. A plain vanilla 1.8 with 126000 miles on the clock and ‘patina’ so not worth much. Many thanks to advice from a N Birmingham VMCC section member on one of our Zoom coffee mornings. A breaker bar plus that vital ‘snatch’ loosened the crank pulley bolt OK. The complicated bit went fine (practice on Gilera Bialbero motorcycle motors), though I resorted to the zip tying the belt to the exhaust cam sprocket dodge while putting the new belt on. The job included dealing with the seized and snapped off lower cam belt cover set screws. The last person (professional) to change the belt had just cracked the plastic cover off them to get if free. I did a cunning fix using short lengths of motorcycle control cable ferrule over the remaining threads as spacers and M6 socket head sleeve nuts to hold the new pattern cover on. Less fraught than trying to get the remains of the screws out. During reassembly, however, I noticed a small spigot on a cooling system connection (water pump inlet pipe) had rusted to the point of imminent failure so more grovelling under it required yet. I really hate working on cars, but given its crusty under body it’s just not worth spending too much on as I suspect its life is limited. My lockdown time is free, though, and I have a strict parts budget limit that hasn’t been exceeded yet. A new part is £100 from MX5 parts, so might search for a usable pre-loved one. First I need to get the old one off completely!

Sounds like you’re having fun? :+1: have a look here, a common issue, certainly wont cost much if you have some tools handy.

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Great. Verging on scrap box engineering.
The T piece on my thermostat housing is looking a bit dodgy but it’s the ‘elbow’ on the water pump inlet pipe lower down (the other end of the one hose) that has gone.
You have made me think though. Once I have got it off (not relishing the pipe/o-ring joint) I’ll see if a similar approach could be used. I’ll have a look at doing it in place but with car just up on ramps that would be either a stretch from above or too a long a grovel underneath for my bad hip. Once on the bench, just an air-line elbow might do the job if the hose is long enough.

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A used water pump inlet pipe arrived today, It was in as good condition as described and a fraction of the cost of a new one. A good job I tried offering up without a new gasket though. One of the mounting bolts was very hard to unscrew and proved even harder to go back in. Had to get out an M8 tap and clean up the thread using ingenuity, as a tap wrench was impossible. All nice now and just waiting on a new gasket. Also treating it to a new by-pass hose too as the old one is very crusty. I risked firing it up very briefly to check my cam belt work and it passed the test, I might even have it running properly in time to take it off SORN for June.

I perfected my filling station routine today while out to visit somewhere to “enjoy the open air” on my Husky 401 that is still running in. At a local supermarket with only pay at the pump there is no need to even open my flip front helmet. I had a 'coronavirus dedicated credit card; in a plastic bag and an isopropyl alcohol wipe for my hands once I had finished and before putting my bike gloves back on.

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Well it lives. All well except for a slight whine from the alternator. The belt was a bit loose and squealed for a few seconds when I first started up so I tightened it a tad. Might have overdone it a bit. The whine stops if you just lightly press the end of a screwdriver against the tensioning adjuster bolt. I’ll back it off a smidgen. The alternator was rebuilt a couple of years ago by a local place after the case cracked (through bolt rust). It was cheaper than an exchange unit, but perhaps a bearing is on the way out.

Kept within my £100 parts budget though (other than antifreeze). We shall see what the next MoT brings in October. I might even have the new tyres scrubbed in by then…

Glad I did a DIY job. That water pump inlet elbow spigot could have failed at an inconvenient time given the corrosion.